To a shocking shooting in Chicago. An executive angry about being Dou demoted shot the CEO. They had been co-workers and friends for years and ABC's Alex Perez has the story. Reporter: This morning what's being called a case of white collar rage turned deadly sending panic through Chicago's financial district Thursday. Police say it was just before 10:00 A.M. When Tony Defrance, an employee at aerostream took the elevator to the 17th floor and shot his bought boss and friend, company CEO Steven Virginia Loy. How do we incorporate -- Reporter: Seen in this company video. Motive, defranefrances had just been demoted as chief technology officer. He was demoted I believe on Friday based on what we have so far for a one-on-one with the CEO during that one-on-one, he produced a firearm. Reporter: Police say 60-year-old defrances was carrying a gun inside a backpack and went trait to Lavoie's office and then -- There was apparently a struggle over the firearm. Reporter: Defrances shot Lavoie in the Tom and head before killing himself. Terrified employees hearing the gunfire scrambled for cover as authorities arrived. I was actually able to see them pulling out one of the people on a stretcher and put into the ambulance. Reporter: Lavoie, a father of three girls, now in critical condition. This morning employees returning to the office. Shaken by the tragedy that unfolded on the 17th floor. For "Good morning America," Alex Perez, ABC news, Chicago.

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